Confusing standards and conflicting opinions have plagued the field of grounding. One of the most important, but least understood considerations in designing and maintaining electrical systems is the grounding of all components. Low resistance earth grounding is essential for safety and protection of sensitive electronic equipment. It is the basis for any facility’s power quality assurance program.

Effective earth grounding is essential for grounded AC and DC electrical equipment and distribution systems. Effective grounding provides the level of safety required to protect personnel and equipment from shock and fire hazard. The understanding and evaluation of a facility ground system should be part of any power quality assurance program.

Some of the basic requirements of an effective ground system include:

• Limits voltage in a electrical distribution system to definite fixed values
• Limits voltage to within insulation ratings
• Reduces static electricity that may be generated within facilities
• Provides a more stable system with a minimum of transient over voltage and electrical noise
• Provides protection from large electrical disturbances (such as lightning) by creating a low resistive path to earth